Tappet metering disk



p i 69 K. w. LESHER 3,439,660

TAPPET METERING DISK Filed May 19, 1967 Sheet or'sfi/lf/g Zak); W 1 4%fa/far ///amgm April 1969 K w. LIESHEQR 3,439,660

TAPPET METERING DISK .Z-iled ma 19, 1967 Sheet .8 of s April 1959 K. w.LESHER 3,439,660

TAPPET METERING DISK Filed May 19, 1967 iiim0 i Z/k/ K221 United StatesPatent US. "Cl. 123-90 6 Claims ABSTRACT OF THE DISCLOSURE The devicedisclosed comprises a hollow hydraulic tappet, to the interior of whichlubricant is conducted from the engine in which the tappet ispositioned. Lubricant fluid is discharged from the hydraulic tappettoward the valve operating means and furnishes lubrication to the valveoperating means including the rocker arm and associated parts. Thetappet disclosed is associated with a hollow pushrod which leads to therocker arm which moves an engine valve. Means are provided in the tappetto meter the flow of lubricant to the pushrod. This means comprises agenerally flat disk provided on each face with a ring-like raisedportion which is shaped with a gap or open space in the ring. The endsof the ring are separated. They overlap each other in one form. Therings are of non-uniform radial disposition with respect to the disk. Aflat seat for the disk is provided within the tappet about the openingthrough which lubricant flows to the pushrod. When the disk is seated onthe seat, lubricant can flow outwardly only through the gap between theends of the ring and it is metered by the size of the gap between theends of the ring.

This invention relates to improvements in a hydraulic tappet andparticularly to hydraulic tappets characterized by metering means formetering lubricant fluid as it moves from the tappet to a point wherelubrication is required.

The invention has for one object to provide a metering assembly in ahydraulic tappet which provides means for controlling the lubricantwhich can flow from the interior of the tappet to a pushrod of alubricating system.

A still further object is to provide a metering disk upon which seatingportions are formed and arranged so that wear between the seatingportions and the seat upon which they sit is widely distributed and isnot concentrated in a pattern identical with the pattern or plan of theseating portions of the tappet.

A further object is to provide a metering disk with the properties abovementioned and provided with seating portions on each side so that it isimmaterial which side of the disk faces the seating portion within thetappet on which the disk is seated.

Other objects will appear from time to time in the followingspecification and claims.

The invention is illustrated diagrammatically in the accompanyingdrawings wherein:

FIGURE 1 is a sectional view through a conventional engine and valveoperating gear showing a hydraulic tappet in position in the valveoperating means,

FIGURE 2 is a vertical section on an enlarged scale showing the tappetof this invention,

FIGURE 3 is a plan view of one form of the disk,

FIGURE 4 is a transverse section taken at line 44 of FIGURE 3,

FIGURE 5 is a plan view of a modified form of disk embodying theinvention,

FIGURE 6 is a transverse section taken at line 6-6 of FIGURE 5,

FIGURE 7 is a plan view of a further modification of the disk,

FIGURE 8 is a transverse section taken at line 8-8 of FIGURE 7,

FIGURE 9 is a plan view of a further modification in which the seatingportion is in the form of an ellipse, and

FIGURE 10 is a transverse section taken at line 10 10 of FIGURE 9.

Like numerals will be used to describe like parts in the followingdescription of the drawings.

The invention is illustrated in FIGURE 1 in a conventional internalcombustion engine comprising a cylinder 1, a cylinder head 2, a valve 3,a valve spring 4, and a rocker arm 5, supported at 6 upon a stud 7. Therocker arm is adapted to be moved by a hollow pushrod 8 which is seatedin a cup 9, having an orifice 10 formed in it. The cup is positioned inthe hollow plunger 11 of a hydraulic tappet. It is mounted forreciprocation within a tappet cylinder or barrel which is provided witha closed bottom 13. The barrel 12 is perforated at 14 to permit enginelubricant to enter the tappet. The barrel is also perforated at 15 andis enlarged at 16 and shouldered at 17. The plunger may be reduced inexternal diameter at its inner end at 18 and may be providedintermediate its ends with a groove or channel 19 from which aperforation or passage 20 leads to the hollow interior 21 of theplunger.

At its inner end, the tappet plunger is provided with an opening 22which may be closed by a valve 23 held in suitable relationship to theinner end of the plunger by a valve cage 24 which has openings 25 in itssides. It is also open at its bottom 26.

A spring 27, positioned within the barrel 12 and beneath the plunger 11,bears against a flange 28 of the valve cage 24 and is biased to move theplunger to the outermost position away from the closed bottom 13.Although the valve cage 24 is positioned upon the reduced extension 29'of the plunger 11 with a press fit, should any looseness occur, it willbe held in position by the contact of the spring 27 with the flange 28.

A locking ring 30 is positioned in a suitable groove adjacent the openend 31 of the tappet barrel 12 and prevents accidental displacement ofthe plunger from the barrel.

A spring 32 may be positioned between the disk 23 and an adjacentportion of the valve cage 24. If present, it will be biased to move thevalve 23 to the seating position of FIGURE 2.

The inner face of the cuplike member is provided with a flat seat 33,against which the seating portion of the disk 34 is adapted to seat toproduce the metering etfect.

Any of the forms of disks shown in the drawings herewith may be used toeffect metering. Each is held at a position adjacent the seat 33 by theshoulder 35 formed in the plunger 11. Several disks will be described indetail in connection with FIGURES 3 to 10 inclusive.

All reference numerals have not been applied to FIG- URE 1 because ofthe relatively small scale of the figure. The reference numerals areapplied to FIGURES 2 to 10 inclusive and are used in the detaileddiscussion of these figures.

All of the forms of disks shown have a common important feature, namelythat each disk is provided with two seating portions adapted to beseated against the seat 33. The two seating portions of each disk arepositioned one on each face of the disk. This is clear, for example,from FIGURE 4 and other sectional views of disks. It is obvious thatonly one seating portion of a disk can be seated against the seat 33.The reason for two seating portions is that in assembly, if there werebut one seating portion or ringlike member, the disk might be improperlyassembled so that its single ringlike seating portion would be facedaway from the seat 33. Should that occur, the disk when seated would notcarry out a metering effect but would simply close the passage 10. Byproviding a seating portion or ringlike member on each face of the disk,it is certain that one of such seating portions will always be inopposition to the seat 33 and when the disk is moved to the seatingportion, the ringlike portion will seat upon the seat 33 and themetering opening will be available to carry out the metering function.Only one of the ringlike seating portions can seat at a time. The otheris merely to make sure that a metering part will always be in contactwith the seat 33 when the disk has been moved to contact that seat.

The contact of the disk with the seat 33 is limited to the ringlike orC-like member on whichever side of the disk is facing the seat 33. Inall forms of the disks, there is thus on each face of the disk a more orless C-like member whose ends do not meet. There is thus providedbetween the ends of each C-like member a gap which is effective as themetering gap.

A problem which is encountered in the use of the metering valve shown isthat the metering valve will inevitably shift and rotate so that ineffect its rotary movement, in whatever direction it takes place, willgradually wear the seat 33. When this occurs, there is always thepossibility that the raised C portion will penetrate into a worn portionon the seat 33 and will thus reduce the clearance through the meteringopening. It is one of the objects of the various structures shown todistribute the wear to as wide an area as possible over the surface ofthe flat seat 33. To accomplish this purpose, the raised seatingportions or C-like members may be positioned not concentric with thedisk or they may themselves be noncircular in plan so as to be ofnonuniform radius from the center of the disk. In either arrangement, awider surface is presented to the flat seat 33 when the disk is in themetering position and therefore in contact with the seat. Thus the wearof the disk on the seat is more widely distributed than otherwise wouldbe the case.

The disk is generally identified by the numeral 34. The modifications,since they are embodied in the C-like or ringlike seating portions areindicated by different numerals.

In the forms of FIGURES 3 and 4, the seating portions comprise C-likemembers 36 and 37 positioned, as shown particularly in FIGURE 4, onopposing faces of the disk. These two portions 36 and 37 are providedrespectively with flattened seating faces 38 and 39. Each has a gap ormetering opening. The C-ring 36 has a metering opening 40 and the C-ring37 has a metering opening 41.

The C-ring of FIGURES 3 and 4, although concentric with each other, arenot concentric with the disk 34. An inspection of FIGURE 3 makes itclear that the outer C-ring 37 is closer to the periphery of the disk 34at the lower side of FIGURE 3 than at its upper side of the figure. Thisarrangement of the C-rings results in spreading the Wear on the seat 33over a wider area than is the case when the C-rings are concentric withthe disk in which they are formed.

The precise contour of the Crings 36 and 37 of FIG- URES 3 and 4 is nota limiting factor of the invention because the arrangement of C-rings sothat they will not be concentric with the disk in which they are formedcan be carried out no matter what the precise shape or contour of theC-rings may be.

As shown in FIGURES and 6, a modified construction appears in which theC-rings are circular and concentric with each other and with the disk inwhich they are formed and the raised portions are therefore of uniformradial disposition with respect to the disk. Thus the disk 42 has aC-ring 43 in one surface and a C-ring 44 in the other surface. TheC-ring 43 defines a metering opening 45 and the C-ring 44 defines ametering opening 46. The difference between the contours or shapes ofthe C-rings 43 and 44 and those of FIGURES 3 and 4 is merelyillustrative of the fact that the rings may take many different formswithout departing from the spirit of the invention and while it ispreferable that the rings be not concentric with the disk, it isrecognized that that arrangement is possible. The invention is,therefore, not limited to any particular shape of C-ring or equivalentmember.

In the form of FIGURE 7, the contour of the C-rings is substantially thesame as that of FIGURES 5 and 6, although they are not identical. In theform of FIGURES 7 and 8, the disk 47 carries on one face a C-ring 48 andon the opposite face, a C-ring 49. Metering openings 50 and 51 areformed respectively in the C-rings 48 and 49'. From an inspection ofFIGURE 7 in particular, it is obvious that the C-rings in that form ofthe invention are not concentric with the disk 47. Hence, thearrangement of the C-rings in the form shown in FIGURES 7 and 8 isessentially the same as that shown in 3 and 4 in which the rings are notconcentric with the disk in which they are formed.

In the form of FIGURES 9 and 10, the disk is provided with C-rings whichare not circular in plan. As shown, they are elliptical. The inventionis not limited to any particular type of curved shape or arrangement ofC-rings. In fact it is not limited to curved seating members at all.However, as shown in FIGURES 9 and 10, the disk 52 has formed on onesurface a C-ring 53 which provides a metering opening 54- and on itsopposite surface the disk 52 has formed a C-ring 55 which providesbetween its ends a metering opening or gap 56.

As is the case with all of the forms of metering disks shown, a ring orringlike member is formed on each face of the disk and only one at atime can be seated against the seat 33. The form of FIGURES 9 and 10 mayhave the rings 53 and 55 formed concentric with each other or they maynot be concentric. They may be concentric with the disk 52 or they maynot be.

One of the advantages of the form shown in FIGURES 9 and 10 is thatsince the C-rings are elliptical rather than truly circular, whateverwear will occur on the seat due to rotation of the disk is spread over arelatively wider area than would be the case if the rings were circularand were also concentric with the circular disk. Therefore, the form ofFIGURES 9 and 10 accomplish the purpose of spreading wear on the seat33' in the same manner as do the forms of FIGURES 3 and 7.

I claim:

1. In combination in a hydraulic valve lifter,

a barrel and a plunger mounted therein for reciprocation,

a pushrod receiving member in said plunger,

a lubricant passage through the wall of said barrel and through the wallof said plunger and through said pushrod receiving member, and

means for controlling the flow of fluid through said last mentionedpassage,

said means comprising a valve seat about said passage and a relativelyfiat valve disk movably mounted adjacent said valve seat and provided oneach surface with a raised seating portion and a metering passage formedthrough each of said seating portions,

said raised seating portions being of nonuniform radial disposition withrespect to the center of said disk.

2. The combination of claim 1 further characterized by the fact that theraised seating portions of the valve disk are noncircular.

3. The combination of claim -1 further characterized by the fact thatthe raised seating portions are nonconcentric with said disk.

4. In combination in a hydraulic valve lifter,

a barrel and a plunger mounted therein for reciprocation,

a pushrod receiving member in said plunger,

a lubricant passage through the wall of said barrel and through the wallof said plunger and through said pushrod receiving member, and

3,439,660 5 6 means for controlling the flow of fluid through said factthat the raised portions are out of center with respect last mentioned aage, to the plan of the valve disk. said means comprising a valve seatabout said passage The CQmbiPatiOII of claim 4 chafacterized y f d arelatively fi t valve disk movably mounted fact that the raised portionsare nonclrcular and posiadjacent Said valve seat and provided on eachSup 5 tloned upon the valve disk concentrically wlth respect to facewith a raised seating portion and a metering the plan of the disk Splassagedformted throuigolileach 0; said selzraltingspgltioins,References Cited at raise sea lng por s corn r1s1ng can 0 1S- tributingthe wear of the raised portion upon the UNITED STATES PATENTS valve seatover an area greater than that of the con- 10 1,899,251 2/ 1933 Zerk13842 X tacting area of the raised portion, said means com- 2,840,063 6/1958 Pllr as. prising the arrangement of the raised portion upon3,273,547 9/ 1966 Leshen the valve disk such that the radius of theraised portion with respect to the center of the disk is non- 15 ALLAWRENCE SMITH 'i Exammer' uniform. US. Cl. X.R.

5. The combination of claim 4 characterized by the

